Overvolting a minn kota trolling motor

With the Minn Kota 30lb 12V
On 24V LiFePo4
Running no seals with salt water on the commutator
Starting with half cooked brushes
Dragging 200 lb
Stock prop

* Got 100m out and back

The next thing I'm going to do (to hit my 2-mile target...)
* Cut down the prop to account for double RPM
* Try running some oil in the motor that gets changed out

Yeah I've been looking at the BLDC setups, before I go brushless I want to try to go 2 mi in saltwater on 8S without significant wear.


My tip for the day is to be careful if you seal the motor assembly. It draws more water in if the top can't breathe.

-methods
 
Previous Attempts and Learning Exercises

Inspiration and First Build

Version 1.0 Build and Testing

Version 2.0 Build and Testing

Version 2.1 Build and Testing

Version 3.0 Build and Testing

Version 3.1 Build and Testing

-methods
 
Guys who are running 12 volts are running this APC prop. It's actually a marine pusher, I thought they were just using a floppy plane prop

It's harder to measure RPM in a... So I'm currently trying to figure out how I'm going to prop down to account for my increased RPM.

* I have the stock prop
* The prop below is comparable
* I doubled my voltage... Now what do I do?

... I'm going to start by cutting down the diameter while watching the current draw, thrust, and top speed achieved under load...

Live the dream

-methods
 

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Thought Process
* Trolling motor props are a nightmare of marked up junk
* Something like 50 bucks, easy

* The APC props can be an order of magnitude cheaper
* I'm thinking I will buy 10... Cut them down 1 cm at a time

From those learnings I'll pick more or less pitch, buy 10 more. There are plenty of simulators in the RC flight industry, I've heard of a few in marine... But there's just too many variables with the hull and the drag

* Velocity cubed instead of velocity squared

Now I get what Jeremy was talking about a decade ago. Sometimes it takes that long.

IIRC
He shared that the best thing you could do was slow it down and run a taller prop for efficiency

I want to figure out what we should do to rip as hard as possible, be damned efficiency.

The lightweight RC boat guys are running 30, 000 and 40,000 RPM on tiny props. They are horrifically noisy.

The hydrofoil guys seem to have figured it out... But they have significantly less drag... So most of their setups won't really work for just dragging dead weight.

There's really no way around the inefficiency cost of dragging through the water... So I either have to switch to hydrofoil, Get more weight on top of the water, or go 10x on power.

Just to be obnox... I'm now seeing 6S 100C Batteries on sale for between 30 and 50 bucks. I might just build one that only runs for a few minutes to have the experience. That was my original intent with my e-bike... BUT IT BECAME RELIABLE (sigh).

For eBikes its high voltage with low KV, If direct drive, for me. For boats? Sigh... More power since there's plenty of cooling.

My boat that satisfies me has a 5.8L V8 direct drive. I've got a lot less drag and weight than that beast... I'm thinking 42 horsepower should do it.

-methods
 
I recentely bought a Minn Kota Endura C2 34lbs trolling motor for my boat. It runs of a 12V battery. I was wondering how it would react if i boost the voltage to maybe 20-24V. Any googling did not really put up results. I am not planning on actually doing it but i am curious.
Anyone of you have an idea?
Boost it up, Bubba! :LOL:
 
Only problem I see with Up Volting cheap DC trolling motors is the windings loop out of
their slots then clash with the magnets from the higher rpm (centrifugal force).
Ive potted my windings in the cat motor then have to balance it.
 
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